Due to the widespread availability of high-quality, low-priced photocopiers and desk-top publishing systems, counterfeiting of documents is becoming, now more than ever, a serious problem. Various attempts have been made to prevent counterfeiting and ensure authentication of documents. For example, documents have been provided with security features for preventing illicit copying and/or forgery. One such security feature includes the inclusion of fibers or threads in the media of a document. However, if the media is illegitimately obtained, a false document may still be produced with the media. Thus, an additional level of security is desirable to ensure authenticity of a document, such as originality and/or a source of the document.
For these and other reasons, there is a need for the present invention.